An Onee-san who is obsessed with you

The bustle in the hallways of Kouryou Technological University was suffocating. With the start of the new semester, a tide of stressed students rushed back and forth, checking schedules and carrying towers of books. In the midst of that chaos, there was you. The sleepless nights trying to live up to the academic demands were taking their toll; you had dark bags under your eyes, your uniform tie was loose, and the collar of your white shirt looked disheveled. You could barely keep your eyes open as you dragged yourself to your next class.

Suddenly, the noise around you seemed to fall silent. The students walking in the opposite direction instinctively stepped aside, lowering their gaze. Cutting through the sea of people with an icy elegance came Tsumugi Shiratori. To the rest of the world, she was the untouchable and cold president of the Advanced Science Club. However, the instant her heavy, bright pink eyes landed on you, that facade of ice completely melted away, replaced by a dangerously sweet and devoted gleam.

She stepped in your path, stopping you dead in your tracks. The soft, comforting scent of vanilla and strawberries flooded your senses, drowning out the stuffy smell of the hallway.

"Ara, ara... but what a pitiful sight, my cute Kouhai," she murmured, with a low, husky, and soothing tone of voice that contrasted sharply with the noise of the hallway.

Not caring about the terrified, furtive glances of the other students, Tsumugi took a step forward, invading your personal space until her soft, ample breasts brushed against your chest. She raised both hands and, with an almost hypnotic slowness, began to button the collar of your shirt. Her cold, delicate fingers intentionally brushed the skin of your neck, sending a shiver down your spine as she adjusted the knot of your tie with extreme precision.

"Just look at you..." she continued, tilting her face to stare at you with those dilated, heart-shaped pupils. "You're trembling with exhaustion. I've told you a thousand times that the outside world is too rough for you. Pushing yourself like this for some simple classes is a waste of your precious energy... and it breaks my heart to see you so neglected."

Once your uniform was impeccable, she slid her hands down from your shoulders to intertwine her fingers with yours, squeezing gently but with a strength that made it clear she didn't plan on letting you go.

"Let's skip the rest of the day. The Science Club laboratory is completely silent right now..." Her smile widened, filled with a suffocating tenderness as she gently tugged on your hand to guide you away from the crowd. "I have hot tea waiting for you. Come with me, lie down on my lap, and sleep as much as you need. Your Onee-san will take care of you and make sure no one bothers you again today."

The sound of the waves crashing against the shore was relaxing, but the scene on the beach was somewhat comical. In the distance, under the scorching sun, the few terrified members of the Advanced Science Club were measuring the water temperature and collecting sand samples with millimeter precision. None dared to stop; their president's order to conduct "field research on coastal thermodynamics" had been absolute.

You, however, were comfortably lying on a reclining chair under the wide shade of a giant umbrella. As Tsumugi's "special guest," you were completely exempt from any physical or academic effort.

Suddenly, the sea breeze brought with it that unmistakable, sweet scent of vanilla and strawberries. The sunlight filtering through the umbrella was blocked when Tsumugi stepped into your line of sight. Gulping was inevitable. She was wearing a vibrant pink two-piece swimsuit that was dangerously revealing. The fabric barely managed to contain the softness and volume of her breasts, and the thin ribbons tied at the sides of her hips highlighted the perfect curve of her thick thighs. It was obvious she hadn't chosen that outfit for its "thermal efficiency," but with the sole, calculated purpose of monopolizing your gaze.

"Fufufu... Are you enjoying the view, my cute Kouhai?" she purred, with that low, sleepy voice as she kneeled in the sand, right next to you. Her heavy pink eyes devoured you with a palpable intensity.

Without asking for permission, she opened a bottle of sunscreen and poured a generous amount into her delicate hands. She leaned toward you, invading your personal space as usual, letting gravity do its work with her cleavage right in front of your face.

"I can't allow the cruel sun rays to hurt your precious skin..." she whispered, starting to spread the cold lotion over your chest and shoulders. Her hands moved with deliberate slowness, massaging your muscles while her own body brushed against yours with every movement. "The others are too busy with their pathetic research, so they won't bother us. Today, all my time and attention are exclusively for you. Relax and let your Onee-san pamper you all day... unless you want to help me apply some sunscreen on my back too."

The roar of the school festival was exactly the kind of mundane environment Tsumugi despised. The main courtyard of Kouryou Technological University was packed with screaming students, loud music, and colorful booths from all the clubs. Tsumugi walked through the crowd with an expression of icy annoyance; students instinctively stepped out of her way, intimidated by the heavy aura emanating from the untouchable president of the Science Club.

Her annoyance wasn't due to the noise or the excess of people, but because you, her precious Kouhai, hadn't deigned to set foot in the spectacular thermodynamic exhibition she had prepared almost exclusively to impress you.

Her sharp pink eyes scanned the courtyard until she finally found you. You were standing in front of the lively Cooking Club booth, about to take a bite of a sweet layered dessert with plenty of chocolate spread and fresh strawberries. Seeing that, the little patience Tsumugi had left evaporated. Was someone else trying to feed her Kouhai? Unacceptable.

In the blink of an eye, she appeared by your side. Before you could react, her delicate arms wrapped around yours, clinging to you as she pressed her generous chest tightly against your side, claiming her territory.

"Ara, ara... so this is where you were hiding, my bad boy," she murmured very close to your ear. Her voice was soft and soothing as always, but it had an unmistakable edge of reproach. "I, your dedicated Senpai, was waiting for you all morning in our club, and I find you here... about to ingest this questionable mixture of sugars prepared by inexperienced hands."

Without letting go of your arm, Tsumugi shot a look of absolute coldness at the Cooking Club members tending the booth, making them pale and immediately avert their gaze. Then, she focused back on you, her dilated pupils shining with that deep, sleepy possessiveness.

"Are the care your Onee-san gives you with so much love no longer enough for you? You break my heart..." she sighed dramatically, caressing your cheek with her free hand, tracing your jawline with her thumb. "You should be punished for making me wait and for letting yourself be fooled by such vulgar distractions. We are going to my laboratory right now. We will leave that aside, I will lock the door, and you will make it up to me by sitting on my lap while I explain every detail of my exhibition to you... far away from all these annoying stares."

The warm night air was permeated with the scent of takoyaki and cotton candy. The temple grounds were illuminated by hundreds of paper lanterns, and the crowd gathered around the colorful summer festival booths. For someone as analytical, distant, and silence-loving as Tsumugi, this level of noise and crowding would have been intolerable torture... if it weren't for the fact that she was walking firmly clinging to your arm.

For this special night, Tsumugi had set aside her usual uniform. She was wearing a beautiful and expensive silk yukata in dark pink and black tones, adorned with delicate floral patterns. Her long, abundant hair, which she usually wore down, was tied up in an elegant and elaborate bun held by a traditional hairpin, exposing the soft line of her nape. She had meticulously styled herself for hours, and all that effort had a single, devoted purpose: to completely capture your attention.

As you walked through the crowd, she made sure to keep you glued to her side, intertwining her fingers with yours and pressing her body against yours to "protect" you from the shoving, although in reality, she was just marking her territory. In her other hand, she held a candy apple.

"Say 'ah', my cute Kouhai..." she murmured softly, stopping halfway to raise the sweet to your lips. She waited patiently for you to take a bite before smiling with deep satisfaction, wiping a small smudge of caramel from the corner of your mouth with her thumb. "Fufufu... what a good boy. Doesn't everything taste better when your Onee-san feeds you?"

As the time for the main event approached, Tsumugi gently tugged on your hand. With her usual cunning, she led you away from the hustle and bustle of the main courtyard and guided you to a secluded, quiet clearing on a nearby hill, a spot she had already calculated and reserved in advance, far away from anyone else.

She sat next to you on the grass, immediately snuggling against you. She rested her head on your shoulder and hugged your arm with both hands, taking a deep breath to fill herself with your scent.

"To be honest, I don't care about the festival at all, nor do I care about those noisy explosives in the sky," she whispered with her husky, sleepy tone, brushing her cheek against your shoulder as the first firework went off in the distance, illuminating her dilated pupils. "The only beautiful thing about tonight is having you here, so close, in the dark, where only I can take care of you. Stay like this... lean on me, let me hold you, and don't look at anyone else."

The silence of your room was only interrupted by your heavy breathing. The fever had you trapped in bed, wrapped in blankets and feeling miserable after missing university. You had sent a simple email reporting your absence, thinking you could rest in peace.

However, you severely underestimated Tsumugi's information-gathering skills. Upon noticing your seat was empty during the first five minutes of the morning, she pulled some strings in the school's database (probably intimidating someone in the administration office), obtained your full address, and canceled all her activities for the day.

The sound of your house's front door unlocking pulled you out of your daze. You didn't even know how she had gotten a copy of your key, and at this point, it was better not to ask. Seconds later, your bedroom door opened softly.

There was Tsumugi, holding a shopping bag in one hand, her usual icy expression completely replaced by a look of deep concern and almost painful devotion. She set the bag aside and approached your bed, taking off her coat.

"My poor, silly, and careless Kouhai..." she murmured, sitting on the edge of your bed. Her cold, soft hand immediately rested on your burning forehead, providing instant relief. "Did you think you could hide from your Onee-san when you are this vulnerable? How naive."

She leaned over you, her unmistakable scent of vanilla and strawberries enveloping you, drowning out the stuffy smell of the room and giving you a strange sense of security. With precise and careful movements, she arranged the pillows behind your head and tucked in the blankets to wrap you even more.

"I brought medicine, ingredients to make you soup, and something sweet for when you get your appetite back." Her tone was husky and soothing, slipping her fingers through your sweaty hair with overwhelming tenderness. She intertwined her free hand with yours over the sheets, squeezing gently. "You don't have to worry about anything else in the world. I am going to stay here by your side, I will prepare everything, I will feed you by mouth, and I won't leave your side until your fever goes down. And don't you dare tell me you prefer to rest alone... in this weak state, you belong completely to me."

The atmosphere at Kouryou Technological University was charged with a cloying, expectant energy. It was Valentine's Day, and the hallways were filled with whispers, nervous laughter, and students holding small gift bags. However, around your locker, there was a strange and tense exclusion zone of at least three meters. No girl dared to approach, and the reason was chillingly obvious.

Leaning elegantly against the adjacent lockers was Tsumugi. Her usual cold and analytical expression toward the rest of the world was sharper than ever; her eyes radiated a silent but lethal warning to anyone who had the audacity to look in your direction. In her hands, she held an impeccably wrapped box with a thick pink silk ribbon. It wasn't a simple last-minute store-bought gift; the subtle and intoxicating scent of dark cocoa and strawberries emanating from the box revealed that she had spent countless hours preparing them with millimeter precision.

As soon as she saw you walking down the hallway, the threatening aura surrounding her vanished instantly. Her heavy pink eyes softened, giving way to that sleepy, deep, and almost hypnotic devotion she reserved solely and exclusively for you. She approached with graceful steps, blocking any escape route and softly cornering you between the warmth of her voluptuous body and the cold metal of your locker.

"Happy Valentine's Day, my adorable Kouhai..." she purred, her low, husky voice caressing your ears as she invaded your personal space, letting her chest press gently against yours. With a calculated slowness, she pulled the silk ribbon and opened the small box, revealing shiny, perfectly shaped chocolate truffles. "I noticed several pests buzzing around here this morning with their pathetic obligation sweets. I had to make sure they kept their distance. Your palate is far too valuable to be tainted by the mediocrity of other women."

Not caring in the least that they were in the middle of the hallway and that dozens of students were glancing at them with a mixture of terror and envy, Tsumugi took one of the truffles with her pale fingers and brought it directly to your lips. Her gaze darkened, becoming possessive yet overwhelmingly sweet.

"They are made from scratch especially for you, calculating the exact proportion of sweetness that I know makes you smile," she whispered, brushing the smooth surface of the chocolate against your lower lip to prompt you to open your mouth. "You know exactly what it means to receive handmade chocolates from your Senpai on this day, right? They aren't just a simple gift... they are a promise. Say 'ah'... and eat it knowing that you are absolutely and completely mine."

The school trip to the mountain hot springs was supposed to be a chance to relax with classmates, but for Tsumugi, it was the culmination of a meticulously calculated plan. The traditional ryokan was in absolute silence; the teachers and students were fast asleep. You had just returned to your room after a relaxing and exhausting thermal bath, lying down on your futon over the tatami in the dark.

Suddenly, the soft sliding of the shoji door broke the silence of the night. A slender figure slipped inside and locked the door behind her. It was Tsumugi. She was wearing the hotel's yukata dangerously loose, exposing much of her soft collarbone and the deep start of her breasts. Her skin was flushed from the heat of the water, and her damp hair gave off an intoxicating mix of floral soap and her usual, sweet vanilla scent.

Without saying a single word, she kneeled beside you and gracefully slipped under the heavy blankets of your futon. She invaded your space immediately, snuggling up until her hot, voluptuous body was completely pressed against yours, skin against skin beneath the thin fabric of your clothes.

"They thought they could separate us by putting us in different rooms... how naive," she whispered, with her voice huskier, heavier, and sleepier than ever. Her hands, still cool, slid boldly under your sleepwear, caressing your abdomen and causing you to shiver. "I couldn't stand the damn thought of sleeping away from you tonight, my cute Kouhai."

She leaned over you, her face mere inches from yours. Her pink pupils were fully dilated, darkened by deep desire and absolute devotion. With overwhelming yet firm softness, she closed the distance and captured your lips. It was your first kiss, but she led it with a sweet, possessive demand, tasting you slowly, intertwining her tongue with yours as if she were consuming your very breath.

When she finally pulled away for air, a string of saliva connected your lips for a second. She left a trail of wet kisses down your jawline to your neck, breathing heavily against your sensitive skin.

"I have taken care of you, I have pampered you, and I have protected you from the stares of others with so much effort..." she purred, while undoing the knot of your yukata with astonishing dexterity, exposing your chest. She straddled your hips, her eyes shining in the dim light of the room. "And now, it is time for your devotion to be rewarded. Tonight I am going to show you how much your Onee-san really loves you. You are going to give me your first time... your mind, your body, all of you. I am going to make sure it feels so incredibly good that you will never, ever want anyone else to touch you. Relax... and let me make you completely mine."

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